Repeater striking mechanisms are exceptional pieces because of their large number of components and the care and time taken in production and assembly. Striking complications have been known since at least the 18th century, but have only been the subject of a limited number of publications between 1763 and the middle of the 20th century. The reference work well known to the skilled craftsman in complications, in particular large striking and repeater mechanisms, which will be referred to so as not to overload the explanation of the invention, is the treatise “Les montres compliquées” [Complicated watches] written by François Lecoultre and published by Editions horlogères à Bienne. It is completed by the collective work “Théorie d'horlogerie” [Clockmaking Theory] by Messrs. Reymondin, Monnier, Jeanneret, Pelaratti, published by the FET (Fédération des écoles techniques) in Switzerland.
Chiming watches were invented to overcome the lack of night illumination in the past and to know the time at any moment.
Improvements have enabled the performance of tunes, e.g. by juxtaposing sequences in a predetermined order controlled by perforated discs or cylinders or pins such as those used in musical boxes.
However, chiming watches do not yet give all the possibilities provided by visual display watches and in particular the distinction of day/night, morning or afternoon (AM/PM) the distinction between several time zones (GMT) or also the breakdown of time according to particular scales, and as the user chooses.
Document EP 2 498 145 A1 in the name of MONTRES BREGUET S A describes a striking mechanism with differentiated chimes with a repeater striking assembly stage comprising a drive plate with pivoting pipe carrying a click with a beak restored by a spring and movable under the action of a pin of a detent ratchet cooperating with a striking control mechanism, wherein this stage comprises a pipe ratchet pivoting on this pipe to cooperate at the level of a toothing forming part thereof with the beak of the click, which permits or prevents the pivoting movement of the pipe ratchet, which is fixed to a first hour ratchet that cooperates with a first hammer drive lift. This stage comprises a second hour ratchet that pivots around the same axis and cooperates with a hammer drive lift of said striking mechanism.
Document EP 1 770 453 A1 in the name of CHRISTOPHE CLARET S A describes a mechanical timepiece comprising a time display mechanism for a first and a second time zone fitted with a striking device, which allows a chime corresponding to the time of the first or the second time zone to be produced by choice. This striking device is supplied with energy by a single striking barrel controlled by control elements intended to activate a chime corresponding to the time of the first and the second time zone.